Base de dados : MEDLINE
Pesquisa : G05.344.401.501.450 [Categoria DeCS]
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  1 / 1984 MEDLINE  
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[PMID]:29266057
[Au] Autor:Valenzuela NM; Schaub S
[Ad] Endereço:UCLA Immunogenetics Center, Department of Pathology and Laboratory Medicine, University of California, Los Angeles, CA.
[Ti] Título:The Biology of IgG Subclasses and Their Clinical Relevance to Transplantation.
[So] Source:Transplantation;102(1S Suppl 1):S7-S13, 2018 01.
[Is] ISSN:1534-6080
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Immunoglobulin G (IgG) is the dominant immunoglobulin and can be divided into 4 distinct subclasses. The evolution of IgG subclass switches is regulated by interaction with T cells and follows a 1-way direction (IgG3 → IgG1 → IgG2 → IgG4). Based on their structure, the 4 IgG subclasses can initiate different effector function such as complement activation, recruitment of various cells by Fc receptors, and agonistic signaling. Using current assays for HLA antibody detection as a template and replacing the generic reporter antibody with IgG subclass-specific reporter antibodies, it is possible to investigate the IgG subclasses of HLA antibodies. There are 15 different IgG subclass compositions possible. Based on the capability to activate the complement system and the class switch direction, 3 arbitrary patterns can be defined (ie, only complement-binding subclasses [IgG3 and/or IgG1], expansion to noncomplement-binding subclasses [IgG3 and/or IgG1 plus IgG2 and/or IgG4], and switch to noncomplement-binding subclasses [IgG2 and/or IgG4]). The latter group accounts for less than 5%, whereas the former 2 groups have a similar prevalence close to 50%. In the past 5 years, several studies correlated the IgG subclass pattern with occurrence of antibody-mediated rejection and allograft outcomes. Because of differences of the used IgG subclass assay, the time point of analyses, and the definition of outcomes, a clear picture has not emerged yet. Future needs are standardization of the assay, a more detailed knowledge of the initiated effector functions, and more well-designed clinical studies also looking at changes of the IgG subclass pattern over time.
[Mh] Termos MeSH primário: Antígenos HLA/imunologia
Teste de Histocompatibilidade
Switching de Imunoglobulina/imunologia
Imunoglobulina G/imunologia
Isoanticorpos/imunologia
Transplante de Órgãos
[Mh] Termos MeSH secundário: Ativação do Complemento/imunologia
Seres Humanos
Imunoglobulina G/classificação
Imunoglobulina G/genética
Isoanticorpos/classificação
Isoanticorpos/genética
Receptores Fc/imunologia
[Pt] Tipo de publicação:JOURNAL ARTICLE; REVIEW
[Nm] Nome de substância:
0 (HLA Antigens); 0 (Immunoglobulin G); 0 (Isoantibodies); 0 (Receptors, Fc)
[Em] Mês de entrada:1712
[Cu] Atualização por classe:180216
[Lr] Data última revisão:
180216
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171222
[St] Status:MEDLINE
[do] DOI:10.1097/TP.0000000000001816


  2 / 1984 MEDLINE  
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[PMID]:27776452
[Au] Autor:Vo Ngoc DT; Krist L; van Overveld FJ; Rijkers GT
[Ad] Endereço:a Department of Science , University College Roosevelt , Middelburg , The Netherlands.
[Ti] Título:The long and winding road to IgA deficiency: causes and consequences.
[So] Source:Expert Rev Clin Immunol;13(4):371-382, 2017 04.
[Is] ISSN:1744-8409
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:INTRODUCTION: The most common humoral immunodeficiency is IgA deficiency. One of the first papers addressing the cellular and molecular mechanisms underlying IgA deficiency indicated that immature IgA-positive B-lymphocytes are present in these patients. This suggests that the genetic background for IgA is still intact and that class switching can take place. At this moment, it cannot be ruled out that genetic as well as environmental factors are involved. Areas covered: A clinical presentation, the biological functions of IgA, and the management of IgA deficiency are reviewed. In some IgA deficient patients, a relationship with a loss-of-function mutation in the TACI (transmembrane activator and calcium-modulating cyclophilin ligand interaction) gene has been found. Many other genes also have been associated. Gut microbiota are an important environmental trigger for IgA synthesis. Expert commentary: Expression of IgA deficiency is due to both genetic and environmental factors and a role for gut microbiota cannot be excluded.
[Mh] Termos MeSH primário: Linfócitos B/fisiologia
Deficiência de IgA/imunologia
Imunidade nas Mucosas
Imunoglobulina A/metabolismo
Microbiota/imunologia
Células Precursoras de Linfócitos B/fisiologia
Proteína Transmembrana Ativadora e Interagente do CAML/genética
[Mh] Termos MeSH secundário: Animais
Fator Ativador de Células B/genética
Interação Gene-Ambiente
Predisposição Genética para Doença
Seres Humanos
Deficiência de IgA/etiologia
Switching de Imunoglobulina
Polimorfismo Genético
Membro 13 da Superfamília de Ligantes de Fatores de Necrose Tumoral/genética
[Pt] Tipo de publicação:JOURNAL ARTICLE; REVIEW
[Nm] Nome de substância:
0 (B-Cell Activating Factor); 0 (Immunoglobulin A); 0 (TNFRSF13B protein, human); 0 (Transmembrane Activator and CAML Interactor Protein); 0 (Tumor Necrosis Factor Ligand Superfamily Member 13)
[Em] Mês de entrada:1706
[Cu] Atualização por classe:180215
[Lr] Data última revisão:
180215
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:161026
[St] Status:MEDLINE
[do] DOI:10.1080/1744666X.2017.1248410


  3 / 1984 MEDLINE  
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[PMID]:28461573
[Au] Autor:Ratiu JJ; Racine JJ; Hasham MG; Wang Q; Branca JA; Chapman HD; Zhu J; Donghia N; Philip V; Schott WH; Wasserfall C; Atkinson MA; Mills KD; Leeth CM; Serreze DV
[Ad] Endereço:The Jackson Laboratory, Bar Harbor, ME 04609.
[Ti] Título:Genetic and Small Molecule Disruption of the AID/RAD51 Axis Similarly Protects Nonobese Diabetic Mice from Type 1 Diabetes through Expansion of Regulatory B Lymphocytes.
[So] Source:J Immunol;198(11):4255-4267, 2017 06 01.
[Is] ISSN:1550-6606
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:B lymphocytes play a key role in type 1 diabetes (T1D) development by serving as a subset of APCs preferentially supporting the expansion of autoreactive pathogenic T cells. As a result of their pathogenic importance, B lymphocyte-targeted therapies have received considerable interest as potential T1D interventions. Unfortunately, the B lymphocyte-directed T1D interventions tested to date failed to halt ß cell demise. IgG autoantibodies marking humans at future risk for T1D indicate that B lymphocytes producing them have undergone the affinity-maturation processes of class switch recombination and, possibly, somatic hypermutation. This study found that CRISPR/Cas9-mediated ablation of the activation-induced cytidine deaminase gene required for class switch recombination/somatic hypermutation induction inhibits T1D development in the NOD mouse model. The activation-induced cytidine deaminase protein induces genome-wide DNA breaks that, if not repaired through RAD51-mediated homologous recombination, result in B lymphocyte death. Treatment with the RAD51 inhibitor 4,4'-diisothiocyanatostilbene-2, 2'-disulfonic acid also strongly inhibited T1D development in NOD mice. The genetic and small molecule-targeting approaches expanded CD73 B lymphocytes that exert regulatory activity suppressing diabetogenic T cell responses. Hence, an initial CRISPR/Cas9-mediated genetic modification approach has identified the AID/RAD51 axis as a target for a potentially clinically translatable pharmacological approach that can block T1D development by converting B lymphocytes to a disease-inhibitory CD73 regulatory state.
[Mh] Termos MeSH primário: Linfócitos B Reguladores/imunologia
Proteínas de Transporte/antagonistas & inibidores
Citidina Desaminase/antagonistas & inibidores
Diabetes Mellitus Tipo 1/imunologia
Diabetes Mellitus Tipo 1/prevenção & controle
Ativação Linfocitária
Proteínas Nucleares/antagonistas & inibidores
[Mh] Termos MeSH secundário: Ácido 4,4'-Di-Isotiocianoestilbeno-2,2'-Dissulfônico/farmacologia
5'-Nucleotidase/imunologia
Animais
Autoanticorpos/imunologia
Sistemas CRISPR-Cas
Proteínas de Transporte/genética
Proteínas de Transporte/metabolismo
Citidina Desaminase/genética
Citidina Desaminase/metabolismo
Diabetes Mellitus Experimental
Switching de Imunoglobulina
Camundongos
Camundongos Endogâmicos NOD
Proteínas Nucleares/deficiência
Proteínas Nucleares/genética
Proteínas Nucleares/metabolismo
Hipermutação Somática de Imunoglobulina
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, N.I.H., EXTRAMURAL; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Autoantibodies); 0 (Carrier Proteins); 0 (Nuclear Proteins); 0 (Rad51ap1 protein, mouse); EC 3.1.3.5 (5'-Nucleotidase); EC 3.5.4.- (AICDA (activation-induced cytidine deaminase)); EC 3.5.4.5 (Cytidine Deaminase); Q1O6DSW23R (4,4'-Diisothiocyanostilbene-2,2'-Disulfonic Acid)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:180127
[Lr] Data última revisão:
180127
[Sb] Subgrupo de revista:AIM; IM
[Da] Data de entrada para processamento:170503
[St] Status:MEDLINE
[do] DOI:10.4049/jimmunol.1700024


  4 / 1984 MEDLINE  
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[PMID]:28863472
[Au] Autor:McElroy AK; Akondy RS; Harmon JR; Ellebedy AH; Cannon D; Klena JD; Sidney J; Sette A; Mehta AK; Kraft CS; Lyon MG; Varkey JB; Ribner BS; Nichol ST; Spiropoulou CF
[Ad] Endereço:Departments of Pediatrics.
[Ti] Título:A Case of Human Lassa Virus Infection With Robust Acute T-Cell Activation and Long-Term Virus-Specific T-Cell Responses.
[So] Source:J Infect Dis;215(12):1862-1872, 2017 Jun 15.
[Is] ISSN:1537-6613
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:A nurse who acquired Lassa virus infection in Togo in the spring of 2016 was repatriated to the United States for care at Emory University Hospital. Serial sampling from this patient permitted the characterization of several aspects of the innate and cellular immune responses to Lassa virus. Although most of the immune responses correlated with the kinetics of viremia resolution, the CD8 T-cell response was of surprisingly high magnitude and prolonged duration, implying prolonged presentation of viral antigens. Indeed, long after viremia resolution, there was persistent viral RNA detected in the semen of the patient, accompanied by epididymitis, suggesting the male reproductive tract as 1 site of antigen persistence. Consistent with the magnitude of acute T-cell responses, the patient ultimately developed long-term, polyfunctional memory T-cell responses to Lassa virus.
[Mh] Termos MeSH primário: Anticorpos Antivirais/sangue
Linfócitos T CD8-Positivos/imunologia
Imunidade Celular
Febre Lassa/imunologia
Vírus Lassa/imunologia
Vírus Lassa/isolamento & purificação
[Mh] Termos MeSH secundário: Adulto
Amidas/uso terapêutico
Antígenos Virais/imunologia
Antivirais/uso terapêutico
Ensaio de Imunoadsorção Enzimática
Seres Humanos
Switching de Imunoglobulina/genética
Febre Lassa/sangue
Ativação Linfocitária
Masculino
Pirazinas/uso terapêutico
Ribavirina/uso terapêutico
Viremia/sangue
[Pt] Tipo de publicação:CASE REPORTS; JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Amides); 0 (Antibodies, Viral); 0 (Antigens, Viral); 0 (Antiviral Agents); 0 (Pyrazines); 49717AWG6K (Ribavirin); EW5GL2X7E0 (favipiravir)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170907
[Lr] Data última revisão:
170907
[Sb] Subgrupo de revista:AIM; IM
[Da] Data de entrada para processamento:170903
[St] Status:MEDLINE
[do] DOI:10.1093/infdis/jix201


  5 / 1984 MEDLINE  
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[PMID]:28850584
[Au] Autor:Turner JS; Benet ZL; Grigorova I
[Ad] Endereço:Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, Michigan, United States of America.
[Ti] Título:Transiently antigen primed B cells can generate multiple subsets of memory cells.
[So] Source:PLoS One;12(8):e0183877, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Memory B cells are long-lived cells that generate a more vigorous response upon recognition of antigen (Ag) and T cell help than naïve B cells and ensure maintenance of durable humoral immunity. Functionally distinct subsets of murine memory B cells have been identified based on isotype switching of BCRs and surface expression of the co-stimulatory molecule CD80 and co-inhibitory molecule PD-L2. Memory B cells in a subpopulation with low surface expression of CD80 and PD-L2 are predominantly non-isotype switched and can be efficiently recruited into germinal centers (GCs) in secondary responses. In contrast, a CD80 and PD-L2 positive subset arises predominantly from GCs and can quickly differentiate into antibody-secreting plasma cells (PCs). Here we demonstrate that single transient acquisition of Ag by B cells may be sufficient for their long-term participation in GC responses and for development of various memory B cell subsets including CD80 and PD-L2 positive effector-like memory cells that rapidly differentiate into class-switched PCs during recall responses.
[Mh] Termos MeSH primário: Subpopulações de Linfócitos B/imunologia
Linfócitos B/imunologia
Diferenciação Celular/fisiologia
Memória Imunológica
[Mh] Termos MeSH secundário: Animais
Subpopulações de Linfócitos B/metabolismo
Linfócitos B/metabolismo
Antígeno B7-1/metabolismo
Centro Germinativo/imunologia
Switching de Imunoglobulina
Masculino
Camundongos
Plasmócitos/imunologia
Plasmócitos/metabolismo
Proteína 2 Ligante de Morte Celular Programada 1/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (B7-1 Antigen); 0 (Programmed Cell Death 1 Ligand 2 Protein)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171116
[Lr] Data última revisão:
171116
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170830
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0183877


  6 / 1984 MEDLINE  
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[PMID]:28777947
[Au] Autor:Pucella JN; Chaudhuri J
[Ad] Endereço:Immunology Program, Gerstner Sloan Kettering Graduate School of Biomedical Sciences, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA.
[Ti] Título:AID Invited to the G4 Summit.
[So] Source:Mol Cell;67(3):355-357, 2017 Aug 03.
[Is] ISSN:1097-4164
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:In this issue of Molecular Cell, Qiao et al. (2017) use both biochemical and structural approaches to report AID-preferred nucleic acid substrates, illuminating AID targeting mechanisms during CSR and SHM.
[Mh] Termos MeSH primário: Switching de Imunoglobulina
Hipermutação Somática de Imunoglobulina
[Mh] Termos MeSH secundário: Linfócitos B
Citidina Desaminase/química
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
EC 3.5.4.5 (Cytidine Deaminase)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171026
[Lr] Data última revisão:
171026
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170805
[St] Status:MEDLINE


  7 / 1984 MEDLINE  
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[PMID]:28760881
[Au] Autor:Iacoangeli A; Lui A; Haines A; Ohta Y; Flajnik M; Hsu E
[Ad] Endereço:Tisch Multiple Sclerosis Research Center of New York, New York, NY 10019.
[Ti] Título:Evidence for Ig Light Chain Isotype Exclusion in Shark B Lymphocytes Suggests Ordered Mechanisms.
[So] Source:J Immunol;199(5):1875-1885, 2017 Sep 01.
[Is] ISSN:1550-6606
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Unlike most vertebrates, the shark IgL gene organization precludes secondary rearrangements that delete self-reactive VJ rearranged genes. Nurse sharks express four L chain isotypes, κ, λ, σ, and σ-2, encoded by 35 functional minigenes or clusters. The sequence of gene activation/expression and receptor editing of these isotypes have not been studied. We therefore investigated the extent of isotypic exclusion in separated B cell subpopulations. Surface Ig (sIg)κ-expressing cells, isolated with mAb LK14 that recognizes Cκ, carry predominantly nonproductive rearrangements of other L chain isotypes. Conversely, after depletion with LK14, sIgM cells contained largely nonproductive κ and enrichment for in-frame VJ of the others. Because some isotypic inclusion was observed at the mRNA level, expression in the BCR was examined. Functional λ mRNA was obtained, as expected, from the LK14-depleted population, but was also in sIgκ splenocytes. Whereas λ somatic mutants from the depleted sample displayed evidence of positive selection, the λ genes in sIgκ cells accumulated bystander mutations indicating a failure to express their products at the cell surface in association with the BCR H chain. In conclusion, a shark B cell expresses one L chain isotype at the surface and other isotypes as nonproductive VJ, sterile transcripts, or in-frame VJ whose products may not associate with the H chain. Based on the mRNA content found in the B cell subpopulations, an order of L chain gene activation is suggested as: σ-2 followed by κ, then σ and λ.
[Mh] Termos MeSH primário: Subpopulações de Linfócitos B/fisiologia
Linfócitos B/fisiologia
Proteínas de Peixes/genética
Rearranjo Gênico de Cadeia Leve de Linfócito B
Isotipos de Imunoglobulinas/genética
Cadeias Leves de Imunoglobulina/genética
Receptores de Antígenos de Linfócitos B/genética
Tubarões/imunologia
[Mh] Termos MeSH secundário: Animais
Células Cultivadas
Feminino
Regulação da Expressão Gênica
Loci Gênicos
Estruturas Genéticas
Switching de Imunoglobulina
Masculino
RNA Mensageiro
Vertebrados
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Fish Proteins); 0 (Immunoglobulin Isotypes); 0 (Immunoglobulin Light Chains); 0 (RNA, Messenger); 0 (Receptors, Antigen, B-Cell)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170929
[Lr] Data última revisão:
170929
[Sb] Subgrupo de revista:AIM; IM
[Da] Data de entrada para processamento:170802
[St] Status:MEDLINE
[do] DOI:10.4049/jimmunol.1700762


  8 / 1984 MEDLINE  
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[PMID]:28757211
[Au] Autor:Qiao Q; Wang L; Meng FL; Hwang JK; Alt FW; Wu H
[Ad] Endereço:Program in Cellular and Molecular Medicine, Boston Children's Hospital, Harvard Medical School, Boston, MA 02115, USA; Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02115, USA.
[Ti] Título:AID Recognizes Structured DNA for Class Switch Recombination.
[So] Source:Mol Cell;67(3):361-373.e4, 2017 Aug 03.
[Is] ISSN:1097-4164
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Activation-induced cytidine deaminase (AID) initiates both class switch recombination (CSR) and somatic hypermutation (SHM) in antibody diversification. Mechanisms of AID targeting and catalysis remain elusive despite its critical immunological roles and off-target effects in tumorigenesis. Here, we produced active human AID and revealed its preferred recognition and deamination of structured substrates. G-quadruplex (G4)-containing substrates mimicking the mammalian immunoglobulin switch regions are particularly good AID substrates in vitro. By solving crystal structures of maltose binding protein (MBP)-fused AID alone and in complex with deoxycytidine monophosphate, we surprisingly identify a bifurcated substrate-binding surface that explains structured substrate recognition by capturing two adjacent single-stranded overhangs simultaneously. Moreover, G4 substrates induce cooperative AID oligomerization. Structure-based mutations that disrupt bifurcated substrate recognition or oligomerization both compromise CSR in splenic B cells. Collectively, our data implicate intrinsic preference of AID for structured substrates and uncover the importance of G4 recognition and oligomerization of AID in CSR.
[Mh] Termos MeSH primário: Citidina Desaminase/metabolismo
DNA/metabolismo
Switching de Imunoglobulina
Região de Troca de Imunoglobulinas
Recombinação Genética
[Mh] Termos MeSH secundário: Desaminases APOBEC/genética
Desaminases APOBEC/metabolismo
Animais
Diversidade de Anticorpos
Linfócitos B/enzimologia
Linfócitos B/imunologia
Citidina Desaminase/química
Citidina Desaminase/genética
DNA/química
DNA/genética
Seres Humanos
Camundongos
Modelos Moleculares
Mutação
Conformação de Ácido Nucleico
Ligação Proteica
Conformação Proteica
Baço/enzimologia
Baço/imunologia
Relação Estrutura-Atividade
Especificidade por Substrato
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
9007-49-2 (DNA); EC 3.5.4.- (AICDA (activation-induced cytidine deaminase)); EC 3.5.4.5 (APOBEC Deaminases); EC 3.5.4.5 (Cytidine Deaminase)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:171007
[Lr] Data última revisão:
171007
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170801
[St] Status:MEDLINE


  9 / 1984 MEDLINE  
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[PMID]:28716949
[Au] Autor:Quinlan EM; King JJ; Amemiya CT; Hsu E; Larijani M
[Ad] Endereço:Department of Biomedical Sciences, Faculty of Medicine, Memorial University of Newfoundland, St. John's, NL, Canada.
[Ti] Título:Biochemical Regulatory Features of Activation-Induced Cytidine Deaminase Remain Conserved from Lampreys to Humans.
[So] Source:Mol Cell Biol;37(20), 2017 Oct 15.
[Is] ISSN:1098-5549
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Activation-induced cytidine deaminase (AID) is a genome-mutating enzyme that initiates class switch recombination and somatic hypermutation of antibodies in jawed vertebrates. We previously described the biochemical properties of human AID and found that it is an unusual enzyme in that it exhibits binding affinities for its substrate DNA and catalytic rates several orders of magnitude higher and lower, respectively, than a typical enzyme. Recently, we solved the functional structure of AID and demonstrated that these properties are due to nonspecific DNA binding on its surface, along with a catalytic pocket that predominantly assumes a closed conformation. Here we investigated the biochemical properties of AID from a sea lamprey, nurse shark, tetraodon, and coelacanth: representative species chosen because their lineages diverged at the earliest critical junctures in evolution of adaptive immunity. We found that these earliest-diverged AID orthologs are active cytidine deaminases that exhibit unique substrate specificities and thermosensitivities. Significant amino acid sequence divergence among these AID orthologs is predicted to manifest as notable structural differences. However, despite major differences in sequence specificities, thermosensitivities, and structural features, all orthologs share the unusually high DNA binding affinities and low catalytic rates. This absolute conservation is evidence for biological significance of these unique biochemical properties.
[Mh] Termos MeSH primário: Citidina Desaminase/metabolismo
Switching de Imunoglobulina/imunologia
Lampreias/metabolismo
Especificidade por Substrato/imunologia
[Mh] Termos MeSH secundário: Sequência de Aminoácidos
Animais
DNA/metabolismo
Seres Humanos
Mutação/genética
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
9007-49-2 (DNA); EC 3.5.4.5 (Cytidine Deaminase)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171020
[Lr] Data última revisão:
171020
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170719
[St] Status:MEDLINE


  10 / 1984 MEDLINE  
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[PMID]:28709802
[Au] Autor:Magri G; Comerma L; Pybus M; Sintes J; Lligé D; Segura-Garzón D; Bascones S; Yeste A; Grasset EK; Gutzeit C; Uzzan M; Ramanujam M; van Zelm MC; Albero-González R; Vazquez I; Iglesias M; Serrano S; Márquez L; Mercade E; Mehandru S; Cerutti A
[Ad] Endereço:Program for Inflammatory and Cardiovascular Disorders, Institut Hospital del Mar d'Investigacions Mèdiques (IMIM), Barcelona 08003, Spain. Electronic address: gmagri@imim.es.
[Ti] Título:Human Secretory IgM Emerges from Plasma Cells Clonally Related to Gut Memory B Cells and Targets Highly Diverse Commensals.
[So] Source:Immunity;47(1):118-134.e8, 2017 Jul 18.
[Is] ISSN:1097-4180
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Secretory immunoglobulin A (SIgA) enhances host-microbiota symbiosis, whereas SIgM remains poorly understood. We found that gut IgM plasma cells (PCs) were more abundant in humans than mice and clonally related to a large repertoire of memory IgM B cells disseminated throughout the intestine but rare in systemic lymphoid organs. In addition to sharing a gut-specific gene signature with memory IgA B cells, memory IgM B cells were related to some IgA clonotypes and switched to IgA in response to T cell-independent or T cell-dependent signals. These signals induced abundant IgM which, together with SIgM from clonally affiliated PCs, recognized mucus-embedded commensals. Bacteria recognized by human SIgM were dually coated by SIgA and showed increased richness and diversity compared to IgA-only-coated or uncoated bacteria. Thus, SIgM may emerge from pre-existing memory rather than newly activated naive IgM B cells and could help SIgA to anchor highly diverse commensal communities to mucus.
[Mh] Termos MeSH primário: Angiodisplasia/imunologia
Linfócitos B/imunologia
Neoplasias do Colo/imunologia
Pólipos do Colo/imunologia
Imunoglobulina M/metabolismo
Intestinos/imunologia
Plasmócitos/imunologia
[Mh] Termos MeSH secundário: Adulto
Idoso
Idoso de 80 Anos ou mais
Animais
Células Clonais
Feminino
Microbioma Gastrointestinal/imunologia
Seres Humanos
Imunidade nas Mucosas
Imunoglobulina A/metabolismo
Switching de Imunoglobulina
Memória Imunológica
Intestinos/microbiologia
Masculino
Camundongos
Camundongos Endogâmicos C57BL
Meia-Idade
Simbiose
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Immunoglobulin A); 0 (Immunoglobulin M)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170925
[Lr] Data última revisão:
170925
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170716
[St] Status:MEDLINE



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